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Biomedical subjects

H Hatabu

Publications and source records attributed to H Hatabu.

At least 19 recordsLinked to original sources
PubMed1992

Commitment reversion model of unrestricted cell growth.

Through the analysis of accumulated experimental data of cell growth, a model of unrestricted cell growth is presented here. This model is based hypothetically on the cellular commitment to senescence as in the previously presented commitment theory. Cells are divided into 3 types, namely uncommitted cells, committed cells and terminal cells. The division of an uncommitted cell produces an uncommitted cell itself and a committed cell of the first generation. This committed cell goes through a limited number of cell divisions until the cells become non-dividing terminal cells. It is hypothesized that during a committed cell division, there is a very small probability that an uncommitted cell may be generated. With computer simulations, it is estimated that a committed cell of the first generation may divide around 30 times until they become non-dividing terminal cells, and that the probability of an uncommitted cell regeneration for each committed cell division may be 2(-H). This hypothesis may possibly clarify some aspects of the biological phenomena of cell growth, which can not be explained by the previous commitment theory, such as the growth pattern of cultured diploid cells, cancer initiation and promotion, and cancer progression and metastasis.

Animals↗
PubMed1992

Undifferentiated carcinoma of the thyroid gland: sonographic findings.

We report high resolution sonographic (7.5 MHz) findings in four cases of undifferentiated carcinoma of the thyroid gland. Sonographic findings in these four cases included poorly marginated, hypoechoic masses associated with calcifications, and invasion of adjacent cervical structures. A knowledge of the sonographic features of undifferentiated carcinoma of the thyroid gland is of clinical importance, since the tumour has a grave prognosis, quite different from the relatively favourable prognosis of well differentiated thyroid carcinoma.

Adult↗
PubMed1992

Ga-67 citrate accumulation in adenomatous goiter.

An elderly woman with a diffusely enlarged goiter and multiple miliary nodular lesions on chest x-ray showed Ga-67 accumulation in the right thyroid lobe. Histologic findings obtained after total thyroidectomy and open lung biopsy revealed papillary carcinoma in the left lobe with pulmonary metastases and adenomatous nodules in the right lobe. This is the first report of Ga-67 accumulation in adenomatous goiter.

Adenoma↗
PubMed1992

[Transcatheter arterial infusion of adriamycin-lipiodol suspension to patients with metastatic liver tumor].

Adriamycin-Lipiodol suspension was administered to 44 patients with metastatic liver tumor using the transcatheter arterial infusion method. The result revealed 23% in the over all effect (partial response or more) of the therapy which was evaluated by comparing the CT images of the tumor, 47% in the 25% or more of the decrease of the tumor, and 65%, very effective in the decrease of the smaller tumor (less than 50 cm2). Except for a case of hepatic subcapsular hematoma after the infusion of Adriamycin-Lipiodol suspension, minor complications were experienced such as abdominal pain, slight fever, and so on. No serious exacerbation in liver function test and white blood cell count was noted.

Adult↗
PubMed1991

[Results of radioiodine therapy in 47 patients with distant metastases of differentiated thyroid carcinoma].

In the last ten years, 47 patients with distant metastases of differentiated thyroid carcinoma have been treated with 131I following total thyroidectomy. Post-therapy whole body 131I scans revealed detectable uptake in the metastatic lesions in 23 (62%) of 37 patients with lung metastases, 10 (67%) of 15 patients with bone metastases five (71%) of seven patients with mediastinal metastases, and neither of two patients with brain metastases. The concentration of 131I in the metastases was significantly correlated with serum T3 and T4 concentrations, and inversely correlated with serum TSH concentrations. Most of the patients with a strong positive scan were euthyroid, suggesting that thyroid hormones produced by the tumor compensated for hypothyroidism following total thyroidectomy. There was no significant relationship between serum thyroglobulin concentration during T4 replacement therapy and 131I uptake or the efficacy of therapy. Twenty patients with lung (54%), five with bone (33%), two with mediastinal (29%), and none with brain metastases showed tumor regression after treatment. Significantly increased 131I uptake in lung metastases, better therapeutic results and better prognosis were demonstrated in young patients. In conclusion, age, 131I whole body scanning and serum thyroid hormone concentrations are considered to be useful in predicting the efficacy of 131I treatment for distant metastases, especially in the lung.

Adenocarcinoma↗
PubMed1991

Cystic papillary carcinoma of the thyroid gland: a new sonographic sign.

Cystic thyroid lesions are generally considered to be benign and managed by repeated aspiration and/or biopsy. We report characteristic sonographic signs in eight cases of cystic papillary carcinomas of the thyroid gland. In all eight cases, ultrasonography (US) revealed mostly cystic lesions with solid excrescences protruding into the cyst. These nodules contained multiple punctate echogenic foci suggesting calcification. In three of these cases the initial fine needle aspiration biopsy was negative. The 'calcified nodule in cyst' sign was found to be very specific for cystic thyroid carcinoma in a review of the ultrasound findings in 115 patients with nodular thyroid lesions. Careful evaluation and/or surgery should be recommended in patients who have such characteristic sonographic findings even if the fine needle aspiration result is negative.

Adult↗
PubMed1991

Induction of c-fos and c-myc mRNA expression by immunoglobulin G from patients with Graves' disease in thyrotrophin-dependent rat thyroid cell line (FRTL5).

The present study was conducted to evaluate effects of autoantibodies in patients with Graves' disease on induction of c-fos and c-myc mRNA expression in rat thyroid cell line (FRTL5). IgG fractions were isolated from 11 patients with Graves' disease, and six healthy subjects, with protein A-Sepharose. FRTL5 cells which had been grown to subconfluency and deprived of TSH for a week were exposed to the IgG for an hour. Expression of c-fos and c-myc mRNAs was examined by the Northern blot method using nick-translated v-fos and c-myc probes. C-fos and c-myc transcripts were induced by IgGs from two patients with Graves' disease, which displayed much higher activities in assays for TSH binding inhibitor immunoglobulins, thyroid stimulating antibodies and thyroid growth-stimulating immunoglobulins, assessed by measuring inhibition of 125I-TSH binding to the TSH-receptor, cAMP production and 3H-thymidine incorporation in FRTL5 cells, respectively, compared with those in the remaining patients. The induction of c-fos and c-myc mRNAs by IgG from a patient with Graves' disease was suppressed by preincubation with IgGs from two patients with primary myxoedema who were known to have a blocking type TSH-receptor antibody. These data suggest that the binding of the antibodies to the TSH-receptor followed by cAMP production is related to the induction of c-fos and c-myc mRNAs and, thus, to the growth of FRTL5 cells. To our knowledge, this is the first report demonstrating that autoantibodies induce proto-oncogene mRNA expression.

Adolescent↗
PubMed1991

Lymphoproliferative disorders of the thyroid gland: radiological appearances.

Images of lymphoproliferative disorders of the thyroid by ultrasonography (US), computed tomography (CT), 99Tcm and 67Ga scintigraphy were analysed in eight patients (two men and six women, aged 42-83 years). Seven patients were diagnosed as having primary lymphoma and one plasmacytoma. Ultrasound revealed a solid mass with homogeneous and very low echogenicity clearly distinguishable from residual thyroid tissue in five patients, diffuse hypoechoic goitre in one and multiple irregular hypoechoic nodules in both lobes in the patient with plasmacytoma (Case 8). Computed tomography demonstrated a focal low-density area in six cases of lymphoma and decreased density throughout the gland in the other two patients. 99Tcm scintigraphy showed hemilobar enlargement with decreased and uneven trapping, cold area or complete lobar defect in six patients with lymphoma and no trapping in the case of plasmacytoma. 67Ga scintigraphy demonstrated high accumulation in lymphoma and faint accumulation in the case of plasmacytoma. Radiological manifestations with a focal lesion were considered typical and diagnostic of primary thyroid lymphoma, while in one case with diffuse infiltration through the whole gland, the differential diagnosis from Hashimoto's thyroiditis could not be made. In the final case, cells infiltrated diffusely to form islands with patchy distribution among well preserved follicles, correlating with the multiple hypoechoic areas observed by US.

Adult↗
PubMed1991

Magnetic resonance approaches to the evaluation of pulmonary vascular anatomy and physiology.

MR imaging offers the potential for combined anatomic and flow-related information about the pulmonary circulation. Although conventional spin-echo sequences have provided an accurate and noninvasive means of evaluating the anatomy of the central pulmonary arteries and veins, newer MR techniques--including cine MR, velocity-encoded phase-contrast scans, spatial modulation of magnetization (SPAMM), fast scan techniques with breath-holding, and echo planar imaging in combination with computer-based post-processing--are providing physiological information superimposed on the anatomic maps. This paper reviews these new MR approaches to the integrated anatomic and physiologic imaging of the pulmonary vasculature.

Heart Defects, Congenital↗
PubMed1991

Follow-up study of postoperative patients with thyroid cancer by thallium-201 scintigraphy and serum thyroglobulin measurement.

The utility of 201TI scintigraphy and thyroglobulin measurement in the follow-up observation of postoperative patients with thyroid cancer was evaluated. Thallium-201 scintigraphy was performed in 149 postoperative patients with thyroid cancer. Serum thyroglobulin concentration was concomitantly evaluated in 86 patients. Among 55 patients with positive 201TI scans, 51 patients (92.7%) had recurrent diseases, while 80 of 94 patients (85.1%) with negative scans were free of disease. Twenty-five of 28 patients (89.3%) with elevated thyroglobulin levels were recurrent and 43 of 58 patients (74.1%) with normal thyroglobulin level had no recurrence nor metastasis. All 19 patients with positive 201TI scans and elevated thyroglobulin level had recurrent lesions. Seven of 10 patients with negative 201TI scans and elevated thyroglobulin level showed the presence of metastasis. By concomitant measurement of serum thyroglobulin, more than half of the recurrent patients with negative 201TI scintigraphy were detected. Both 201TI scintigraphy and serum thyroglobulin measurement should be undertaken in the follow-up evaluation of postoperative patients with thyroid cancer.

Adenocarcinoma, Papillary↗
PubMed1990

Sonography of subacute thyroiditis: changes in the findings during the course of the disease.

Fifteen patients with subacute thyroiditis were studied with thyroid sonography. There were local hypoechoic areas in all patients during the active phase of the disease. Among 6 patients who underwent follow-up studies during the course of treatment, 3 had recurrence or aggravation of clinical symptoms such as painful swelling of the thyroid region, which was associated with, and sometimes preceded by, spread or reappearance of the sonographic abnormality. All 6 patients showed complete disappearance of the hypoechoic area when they were in remission. The thyroid sonography is useful not only for the initial diagnosis but also for the follow-up of these patients during the course of the disease.

Adult↗
PubMed1990

Presence of both stimulating and blocking types of TSH-receptor antibodies in sera from three patients with primary hypothyroidism.

A case report of three patients with primary hypothyroidism who had potent TSH-binding inhibitor immunoglobulins (TBII) and both thyroid stimulating (TSAb) and thyroid stimulation-blocking antibodies (TSBAb) has been described. Two patients displayed symptoms and signs indistinguishable from those in primary myxoedema (cases 1 and 2), and another patient had a history of Graves' disease (case 3). TBII, TSAb and TSBAb activities were 90.0, 1084.2 and 94.5% in case 1, 91.5, 826.6 and 95.8% in case 2, 76.0, 230.0 and 95.0% in case 3, respectively (normal range, less than 11.0%, less than 145.0 and less than 22.0%, respectively. The results indicate that both stimulating and blocking types of TSH-receptor antibodies exist in these patients. The possible mechanism whereby hypothyroidism developed has been discussed.

Adolescent↗
PubMed1990

Hepatic neoplasms: effects of transcatheter arterial embolization on coagulation and fibrinolysis.

Forty-eight patients with hepatic malignancy (47 with hepatocellular carcinoma, one with metastatic colon carcinoma), who underwent transcatheter arterial embolization (TAE) for treatment of hepatic neoplasms, were investigated to determine the effects of TAE on coagulation and fibrinolysis. TAE was followed by a significant decrease in the platelet count (P less than .001); a prolongation of prothrombin time (P less than .001); an early increase in levels of fibrinopeptide A (P less than .01), fibrinopeptide B beta-15-42 (P less than .001), and fibrin(ogen) degradation products (P less than .001); and a delayed increase in the fibrinogen level (P less than .001), without a significant prolongation of the activated partial thromboplastin time. In the three patients who developed disseminated intravascular coagulation (DIC) after TAE, a reduction of both the platelet count and fibrinogen level occurred significantly earlier and in a more severe form than in the other patients without DIC; this reduction preceded the onset of the characteristic symptoms of DIC. Data suggested that close monitoring of platelet count and fibrinogen level is important for early detection of DIC following TAE.

Adult↗
PubMed1990

Pulmonary vascular cine MR imaging: a noninvasive approach to dynamic imaging of the pulmonary circulation.

Cine gradient-recalled magnetic resonance (MR) imaging, which has flow sensitivity and high temporal resolution, may potentially yield both morphologic and dynamic flow-related information in the pulmonary vasculature. The authors used this modality to evaluate pulmonary vessels in 12 healthy subjects and in 14 patients with a variety of cardiopulmonary disorders. Normal pulmonary arteries and veins were characterized by distinctive signal intensity and diameter variations as well as motion of the vessels during the cardiac cycle. Patients with pulmonary arterial hypertension demonstrated loss of the normal pulsatile systolic increase and diastolic decline in velocity-related signal intensity and in diameter of the proximal pulmonary arteries. Disorders of pulmonary venous signal and diameter profiles during the cardiac cycle, which show a characteristic biphasic pattern in healthy subjects, were identified in five patients with mitral valvular disease. These initial results indicate that cine MR imaging techniques hold promise in the evaluation of pathophysiologic conditions in the pulmonary circulation.

Adult↗
PubMed1990

Simultaneous measurement of TSH-binding inhibitor immunoglobulin and thyroid stimulating autoantibody activities using cultured FRTL-5 cells in patients with untreated Graves' disease.

A new and practical assay was developed using cultured FRTL-5 cells for simultaneous assessment of TS-ab and TSH-binding inhibitor immunoglobulin, allowing direct comparison of these two activities under the same conditions. Subsequent to the TS-ab assay in which extracellular cAMP concentration in Hanks' medium without NaCl was determined, [125I]b TSH in this medium was added to observe the ability of serum Ig to inhibit the binding of [125I]b TSH to FRTL-5 cells. We found a much higher specific binding of [125I]b TSH to FRTL-5 cells and a much greater inhibition of [125I]bTSH binding to the cells exposed to Graves' Ig in hypotonic NaCl-free than in NaCl containing Hanks' medium, indicating that the binding of both TSH and Graves' Ig to the TSH receptor was salt-sensitive. The inhibitory activity of [125I]bTSH binding to the cells was 0.2 +/- 4.6% (mean +/- SD) in 45 normals. Inter-assay coefficients of variation in two positive controls with the mean values of 18.0 and 65.8% were 15.8 and 16.5%, respectively. Among 46 patients with untreated hyperthyroidism owing to Graves' disease, 45 (97.8%) were positive for TS-ab; 35 (76.1%) and 40 (87.0%) were positive for TSH-binding inhibitor in Ig assays using FRTL-5 cells and solubilized porcine thyroid membranes, respectively. TS-ab activities correlated less closely with TSH-binding inhibitory activities determined using FRTL-5 cells (r = 0.576, p less than 0.001) than with those determined using porcine thyroid membranes (r = 0.745, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗